In the Formula racing world and especially on Formula and racing cars the spring and shock absorber systems are applied according to the MacPherson principle and mostly on the front-wheel suspension. This system is also often used on the front wheels of private cars. The constant improvement of the driving comfort of private cars lead to using spring elements with little self-damping. After an impact the springs oscillate for a long time. Due to this, the wheel can jump up and down, through which the contact with the road is periodically interrupted. The shock absorbers are for damping these movements or, vibrations, as soon as possible. A better word would be vibration damper. The shock absorber is mounted between the wheel suspension and the superstructure or the bodywork. These days almost only hydraulic shock absorbers are used. These are almost always telescopic shock absorbers with an oil-filled tube, in which a, piston with a small bore is movable up and down and so the piston rod moves, which supports the body. The mentioned piston rod is solid and has a circle-shaped. cross-section with a diameter of approximately 18 mm, which for an occurring horizontal load (F) is enough for private cars. The upper side of mentioned piston rod is mounted to the body with an eye structure and the bottom side of the oil-filled and the on both sides closed tube, in which the mentioned drilled piston with piston rod moves up and down, is supplied with stub axle means for mounting to the wheel suspension. Following, according to the MacPherson principle, the shock absorber is provided with a coiled spring so that in one go a spring and damping system is created. This system is economically fabricated and works well on private cars with bend forces transverse to the driving direction of the vehicle.
At the racing sport with Formula cars it appears that when taking turns on an asphalt road or gravel or on damages in the road surface, large forces (F) occur transverse to the tire. Due to this, the shock absorber with coiled spring must transmit a large bend moment vertical on its longitudinal axis, which torque must also be absorbed by the solid piston rod with a diameter of approximately 18 mm. The consequence is a rather large deformation of the longitudinal axis of the piston rod, through which it contacts at a single point of the tube and the piston. Through mentioned deformation the slide or friction resistance of the piston rod and piston is enlarged, through which the shock absorber starts showing blocking properties, which enlarges the brake path and the wheel starts jumping.
For the racing sport as described above the known spring and shock absorbers in Formula sports cars, show a number of disadvantages regarding applicability.